PATCH: ERR_RETURN option

PATCH: ERR_RETURN option

[Peter Stephenson]

I just discovered I needed this --- it works like ERR_EXIT but performs
a `return' instead.  Is this OK?  Have I missed something more obvious?

Index: Doc/Zsh/options.yo
===================================================================
RCS file: /cvsroot/zsh/zsh/Doc/Zsh/options.yo,v
retrieving revision 1.26
diff -u -r1.26 options.yo
--- Doc/Zsh/options.yo	20 Jun 2002 16:39:58 -0000	1.26
+++ Doc/Zsh/options.yo	2 Dec 2002 11:30:35 -0000
@@ -380,6 +380,16 @@
 trap, if set, and exit.  This is disabled while running initialization
 scripts.
 )
+pindex(ERR_RETURN)
+cindex(function return, on error)
+cidnex(return from function, on error)
+item(tt(ERR_RETURN))(
+If a command has a non-zero exit status, return immediately from the
+enclosing function.  The logic is identical to that for tt(ERR_EXIT),
+except that an implicit tt(return) statement is executed instead of an
+tt(exit).  This will trigger an exit at the outermost level of a
+non-interactive script.
+)
 pindex(EXEC)
 cindex(command execution, enabling)
 item(tt(EXEC) (tt(PLUS()n), ksh: tt(PLUS()n)) <D>)(
Index: Src/exec.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/exec.c,v
retrieving revision 1.46
diff -u -r1.46 exec.c
--- Src/exec.c	17 Sep 2002 10:42:20 -0000	1.46
+++ Src/exec.c	2 Dec 2002 11:30:35 -0000
@@ -924,13 +924,23 @@
 		dotrap(SIGZERR);
 		donetrap = 1;
 	    }
-	    if (lastval && isset(ERREXIT)) {
-		if (sigtrapped[SIGEXIT])
-		    dotrap(SIGEXIT);
-		if (mypid != getpid())
-		    _exit(lastval);
-		else
-		    exit(lastval);
+	    if (lastval) {
+		int errreturn = isset(ERRRETURN) && 
+		    (isset(INTERACTIVE) || locallevel || sourcelevel);
+		int errexit = isset(ERREXIT) || 
+		    (isset(ERRRETURN) && !errreturn);
+		if (errexit) {
+		    if (sigtrapped[SIGEXIT])
+			dotrap(SIGEXIT);
+		    if (mypid != getpid())
+			_exit(lastval);
+		    else
+			exit(lastval);
+		}
+		if (errreturn) {
+		    retflag = 1;
+		    breaks = loops;
+		}
 	    }
 	}
 	if (ltype & Z_END)
Index: Src/options.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/options.c,v
retrieving revision 1.13
diff -u -r1.13 options.c
--- Src/options.c	27 Aug 2002 21:10:34 -0000	1.13
+++ Src/options.c	2 Dec 2002 11:30:35 -0000
@@ -109,6 +109,7 @@
 {NULL, "cshnullglob",	      OPT_EMULATE|OPT_CSH,	 CSHNULLGLOB},
 {NULL, "equals",	      OPT_EMULATE|OPT_ZSH,	 EQUALS},
 {NULL, "errexit",	      OPT_EMULATE,		 ERREXIT},
+{NULL, "errreturn",	      OPT_EMULATE,		 ERRRETURN},
 {NULL, "exec",		      OPT_ALL,			 EXECOPT},
 {NULL, "extendedglob",	      OPT_EMULATE,		 EXTENDEDGLOB},
 {NULL, "extendedhistory",     OPT_CSH,			 EXTENDEDHISTORY},
Index: Src/zsh.h
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/zsh.h,v
retrieving revision 1.42
diff -u -r1.42 zsh.h
--- Src/zsh.h	3 Sep 2002 09:33:37 -0000	1.42
+++ Src/zsh.h	2 Dec 2002 11:30:35 -0000
@@ -1419,6 +1419,7 @@
     CSHNULLGLOB,
     EQUALS,
     ERREXIT,
+    ERRRETURN,
     EXECOPT,
     EXTENDEDGLOB,
     EXTENDEDHISTORY,

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR Ltd., Science Park, Milton Road,
Cambridge, CB4 0WH, UK                          Tel: +44 (0)1223 692070


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